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1.
增塑剂对旋转模塑用PVC增塑糊性能的影响   总被引:4,自引:0,他引:4  
通过增塑剂种类及用量对旋转模塑用聚氯乙烯(PVC)增塑糊粘度及其粘度稳定性、脱气性能、凝胶化性能的影响及温度对凝胶化性能的影响进行了研究。结果表明:选择自身粘度较小且溶剂化能力较弱的增塑剂及随增塑剂用量增加,PVC增塑糊粘度下降、粘度稳定性逐渐变好,有利于PVC增塑糊的排气性能提高,延长PVC增塑糊的凝胶化时间。通过调节加热温度及时间可在一定范围内有效控制凝胶化过程,以期获得制品所需性能。  相似文献   

2.
研究了掺混树脂的用量对不同型号的PVC糊树脂发泡性能、黏度、力学性能、加工性能等的影响。结果表明:①对于发泡制品,掺混树脂的最佳替代比例为30%(质量分数);②加入掺混树脂可降低PVC增塑糊的黏度,且在放置时间为24h时黏度最大;③加入掺混树脂会降低PVC增塑糊的力学性能和加工性能。  相似文献   

3.
刘勇  吉玉碧  徐国敏  杨照  赵红波  谭红 《塑料》2012,41(2):78-80,27
采用PVC糊树脂与掺混树脂复配,研究各复配比例下,掺混树脂对增塑糊初始黏度及黏度稳定性、以及糊制品蒸发残渣性能的影响。结果表明:增塑糊初始黏度随掺混树脂比例的增加而逐渐减小;各体系糊黏度稳定性也相应变差,当CPM-31/SB-100=70/30时,PVC增塑糊的黏度稳定性最差,而CPM-31/SB-100=100/0时的黏度稳定性最好;掺混树脂的加入主要影响PVC糊制品在4%乙酸和正己烷浸泡溶剂下的蒸发残渣性能指标,且当掺混树脂含量为10份后两者残渣结果变化趋势相反。  相似文献   

4.
碳酸钙对PVC增塑糊黏度及稳定性的影响研究   总被引:2,自引:0,他引:2  
采用振动黏度计系统研究了碳酸钙粒径大小、含量及颗粒形貌对环保聚氯乙烯(PVC)增塑糊黏度及稳定性的影响规律。结果表明,用4.5um碳酸钙配制的增塑糊初始黏度最大,且黏度稳定性最差;固定PVC树脂为100份时,随碳酸钙含量的增加,增塑糊的初始黏度增大,黏度稳定性降低;固定PVC和碳酸钙粉体总量为120份时,随碳酸钙含量的增加,增塑糊的初始黏度减小,黏度稳定性升高;用规则菱形碳酸钙配制的增塑糊黏度相对较小,用棉絮状碳酸钙配制的增塑糊黏度相对较大,且黏度稳定性最差。  相似文献   

5.
1 概述聚氯乙烯掺混树脂(简称掺混树脂)是一种在配制PVC增塑糊时通过掺混来代替部分糊树脂的PVC树脂。它被广泛用于人造革、壁纸、地板、钢板涂敷、搪塑制品、化学发泡、机械发泡等制品之中。它的主要作用是与糊树脂掺混后降低增塑糊的糊粘度。掺混树脂又可直接烧结制蓄电池隔板。由于掺混树脂能广泛应用于各种硬质、软质的糊树脂制品中,制品质量  相似文献   

6.
选用5种不同牌号的PVC糊树脂制备出增塑糊,研究了PVC糊树脂的颗粒特性对增塑糊陈化行为的影响。结果表明:①小粒子可填充在大粒子之间,从而降低增塑剂的填充量,自由增塑剂更多,成糊后初始黏度较低;②与紧密型糊树脂相比,松散型糊树脂的增塑糊黏度稳定性更好;③分子质量越大,真实密度越大,增塑糊黏度稳定性越好;④对于紧密型糊树脂,低黏度的增塑糊在陈化过程中大粒子会发生沉降,导致糊中粒子分布不均一。  相似文献   

7.
刘岭梅 《中国氯碱》2000,(11):34-35
PVC糊用掺混树脂是一种在配制PVC增塑糊时通过掺混来代替部分糊树脂的PVC树脂,它广泛用于壁纸、地板革、人造革、浸渍制品、注塑制品、搪塑制品的机械发泡、钢板涂层等制品中,不仅能改善糊制品的质量,而且能降低生产成本,提高经济效益。  相似文献   

8.
一、引言 聚氯乙烯(以下简称PVC)增塑糊,是用高分散性PVC树脂微粒加稳定剂等各种添加剂与增塑剂调制成的糊状物。按其实质它是微细的PVC树脂粒子在增塑剂中形成的胶体分散体系。 增塑糊具有独特的加工工艺,它的应用性能主要是涉及到糊的流变性以及糊贮存时期粘度的变化。决定PVC增塑糊流变行为的主要因素是增塑彻中PVC树脂的颗粒大  相似文献   

9.
姚日生 《安徽化工》1990,(4):43-45,4
聚氯乙烯糊用掺混树脂是一种在使用时通过掺混来代替PVC增塑糊中部分糊树脂的PVC树脂。它能降低PVC增塑糊粘度并大幅度降低糊料成本。这种树脂可用悬浮法,本体聚合法进行均聚或共聚制得。B.F.Goodrich公司首先在六十年代利用改进的悬浮法开发了这种产品。此树脂要求粒子最好呈球形、外表光滑、粒度分布窄、平均粒径在10~80μm,且不存在200μm以上的颗粒、K值为57~70;还  相似文献   

10.
本文阐述了聚氯乙烯糊树脂的颗粒结构特征,喷雾干燥和后处理的条件对糊树脂颗粒粒径分布与树脂粉料在增塑剂中解碎难易的影响以及不同增塑糊的流动性能;提出了控制糊粘度的可行性;建立了掺混增塑糊糊粘度计算的经验公式和胶乳粒子准单峰分布的增塑糊牛顿型高剪切极限粘度的数学模型。  相似文献   

11.
The ease with which plasticizer is combined with poly(vinyl chloride) resin is a measure of processing characteristics critical in the dry blending of suspension PVC and the gelation of plastisols. By using commercial grade plasticizers, this study developed predictive equations for the following processing parameters of dialkyl phthalates in PVC:
  • Relative dry-blend rates in suspension PVC as a function of plasticizer viscosity.
  • Relative initial gelation temperatures in plastisols as a function of plasticizer molecular weight and solvating strength.
  • Relative final gelation temperatures in plastisols as a function of plasticizer solvating strength.
This information allows one to predict the relative processing characteristics of any dialkyl phthalate plasticizer for PVC on the basis of its chemical and physical properties.  相似文献   

12.
Different grades of PVC resins and a variety of plasticizers are used to adjust processability and properties of plastisol. The plastisol, which is a dispersion of fine particles of PVC in plasticizer, is coated on a substrate and heated in an oven to gel and fuse. In the gelation stage the resin particles become swollen with plasticizer and then, in the fusion stage the entire system fuses to become one homogeneous phase. The finished products are flexible PVC such as coated fabrics and surgical globes. Different plasticizers, because of the difference in solvent power, affect the process of gelation and fusion, and hence, processability. This paper examines such an effect systematically by employing a homologous series of plasticizers, dialkyl phthalates. The progress of gelation and fusion are followed by the measurements of dynamic moduli and by the observation with a scanning electron microscope. As it may be expected, the shorter the alkyl chain, the higher the solvent power of the plasticizer.  相似文献   

13.
The time for a PVC resin to dry blend or to become a free flowing mix, when blended with a plasticizer in an elevated processing mode, is a common concern for manufacturers of flexible PVC products. The limiting factor in some processes is the dry blending cycle time. Longer dry blending times increase manpower and energy cost per mixer batch. Each flexible PVC compounder has some type of quality control test he uses to assess a resin's dry-up properties. This paper examines the relationship of resin particles and plasticizer during dry-up testing of intermediate to high molecular weight PVC resins. Through this examination, a better understanding of the factors that control dry-up times was achieved. Also included is a comparison of quality control dry-up times and mix cycle times in production size mixers.  相似文献   

14.
This paper reviews the most widely used models for explaining how plasticizers render PVC flexible. These models include the gel, lubricity, and free volume theories; kinetic theories; and mathematical models which predict on the basis of plasticizer structure how much a plasticizer will lower the polymer glass transition in a flexible PVC compound. Since plasticization results from interactions between plasticizer and polymer, methods which have been used to study either the strength or the permanence (or both) of those interactions are also briefly discussed. Tools which have often been used to study plasticizer‐PVC interactions include infrared and nuclear magnetic resonance spectroscopy, compression and humid‐aging tests, dynamic mechanical analysis, torque rheometer tests, plasticizer‐resin clear point temperature measurements, plastisol gelation/fusion by hot stage measurements, and others. J. VINYL ADDIT. TECHNOL., 2009. © 2009 Society of Plastics Engineers  相似文献   

15.
Gelation of PVC solutions is generally agreed to result from network formation. The proposed network linkages include crystallites, hydrogen-bonds, and entanglements brought about by spinodal decomposition. The objective of this work is to relate the phase behavior or compatibility of PVC/plasticizer solutions to their gelation behavior. The thermoreversible sol-gel transition of plasticized PVC was studied using a simultaneous light scattering and dynamic viscoelastic analysis technique, in parallel with a thermal optical analysis (TOA). PVC solutions of 1% to 15% in different types of phthalate and sebecate plasticizers were used. Preliminary results suggest phase separation in the less compatible plasticizer during gelation process while more compatible plasticizer/PVC solutions gel without phase separation. This suggests that the gelation process can be relatively independent of the liquid-liquid phase equilibria in the system.  相似文献   

16.
The phenomenon of plasticizer acceptance by poly(vinyl chloride) (PVC) in hotprocess dry blending is examined via scanning electron microscopy, mercury intrusion porosimetry, and torque rheometer measurements. The effects of granule porosity, resin molecular weight, and synthesis recipe in PVC manufacture by the suspension process are related to the rate of plasticizer acceptance. For a PVC resin to dry blend, i.e., to become a free-flowing powder when mixed with plasticizer under hot-processing conditions, the resin granules must be porous. Porosity arises from interstices between primary PVC particles. At a given granule porosity, an increase in primary particle agglomeration adversely affects dry blend performance. At constant molecular weight and for resins manufactured by a given recipe, dry-blend performance is quantitatively described by granule porosity. With an increase in resin molecular weight, a greater granule porosity is required to maintain an equivalent dry-blend time (DBT). Accordingly, for most suspending agent recipes, DBT is dependent directly upon granule porosity and inversely upon molecular weight. However, if the suspending agent used in resin manufacture is an excessively rapid film former, dry-blend performance with molecular weight variation is dependent upon the suspending agent's concentration, not upon granule porosity, which must be adequate, nor upon the resin's molecular weight. An interfacial film-forming suspending agent enhances fusion of primary PVC particles at the suspension granule—water interface, increasing the granule's “pericellular membrane” thickness. This membrane, a PVC skin, does not significantly influence dry-blend performance with low- or intermediate-viscosity plasticizers. The particle skin does impede dry-blend rates with high-viscosity, poorly solvating plasticizers, but this effect can be negated in part by increasing the diameter of pore openings in the topographical skin. Dry blending occurs below the glass transition temperature (Tg) of PVC with low-viscosity plasticizers and above the Tg with high-viscosity, poorly solvating modifiers. The influence of resin and plasticizer variables indicates the dry-blend phenomenon to be a diffusion-controlled process. The rate of dry blending is dependent upon two mechanisms: (1) the rate of pore penetration—which exposes the plasticizer to a much greater surface area than if it remained exterior, encapsulating the granule—and (2) the rate of plasticizer diffusion into the PVC matrix.  相似文献   

17.
The influence of the crystalline areas observed in poly(vinyl chloride) (PVC) the mechanical and thermal properties of PVC plastisols was studied. Several industrial‐degree PVC resins were used to obtain a broad range of molecular weights and processing conditions for PVC plastisols. The gelation process was fully studied at different temperatures and was related to the existence of crystalline areas at high temperatures, even near the glass transition. A simple explanation of the phenomena observed during the gelation of plasticized PVC is proposed, according to the variation in the mechanical and thermal properties at different temperatures. The final gelation was obtained at 140–150°C, which was a lower temperature than those at the beginning of the thermal degradation process. The thermodynamic aspects of the gelation of plasticized PVC were mainly controlled by the PVC resin properties, whereas the plasticizer only influenced the diffusion and stability of the material. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 538–544, 2004  相似文献   

18.
赵丽颖 《聚氯乙烯》2020,48(3):11-13
针对消光PVC树脂增塑剂吸收量偏低、凝胶含量不稳定等问题,对辅助分散剂种类、消光剂的加入量和加入时间等方面进行了调整,调整后产品凝胶含量批次稳定性提高,树脂内部孔隙疏松,更加有利于增塑剂的吸收。  相似文献   

19.
The behavior of PVC plastisols during gelation and fusion was studied by the ATR-FTIR technique (Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy). DBP, DOP, and DIDP, three common phthalate plasticizers for PVC, were used in plastisols formulations. Three heating rates—5, 10 and 15°C/min—and formulations with different plasticizer concentrations were studied. The IR spectra of a plastisol coincides with the IR spectra of the plasticizer except for the bands at 1435 and 613 cm?1 from the PVC (CH2 wagging and C—Cl stretching, respectively). When the plastisol is heated, a progressive decrease of the plasticizer bands areas can be observed, while bands from PVC increase their intensity, probably because of the adsorption of the plasticizer by the resin. On cooling, the area of all bands follows the same path as when heating, but the paths separate at a certain temperature, showing the irreversible nature of this process. The analysis of the band at 1280 cm?1 (C(O)—O from plasticizer) during heating and cooling, shows that the temperature of separation areas (Ts) takes place at temperatures coherent with plasticizer compatibility. Studies at different heating rates and different plasticizer content are in good agreement with results using other techniques, available in the literature.  相似文献   

20.
主要以高聚合度以及含22%左右凝胶量的聚氯乙烯树脂为研究对象,探讨了不同聚合度的聚氯乙烯树脂、增塑剂、填充剂及加工温度对共混物力学性能及消光性能的影响。  相似文献   

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